Underground pipes are used for, among other things, connecting homes and creating networks for utilities such as sewer, water, gas, electric, telephone, etc. As underground pipes age, they are subject to inevitable deterioration and wear. As a result, underground pipes need to be replaced from time-to-time.
One method for replacing existing underground pipe with replacement pipe is to excavate the entire length of the existing pipe, remove it and place new replacement pipe into the excavation. Drawbacks of such “excavation” method of replacing existing underground pipe are numerous. For example, excavation of existing pipe can be expensive, time-consuming, labor-intensive, and may result in damage to the area surrounding the excavation. In many instances, a main portion of underground pipes lie beneath driveways, buildings, lawns, or gardens, and property owners are often concerned about any damage that may result thereto. In addition, excavation is often made difficult by the presence of other underground utilities.
A technique known as “pipe bursting” may be one way to replace underground pipe without the need to dig up the pipe to be replaced. In pipe bursting, an expander, which is also sometimes referred to as a “mole,” is pulled by a cable, chain, or other similar means through the existing pipe while it is still underground. The body of the expander is typically slightly larger than an inner diameter of the existing pipe. As the expander is pulled, it is designed to break or “burst” the existing underground pipe into many remnants, and at the same time expand the remnants into the surrounding soil. The expansion of the old pipe allows the expander to pull a replacement pipe into place.
A technique known as “pipe splitting” may be another way to replace underground pipe without the need to dig up the pipe to be replaced. In pipe splitting, a pipe splitter is pulled by a cable through the existing pipe while it is still underground. A first portion of the pipe splitter is typically slightly smaller in diameter than the inner diameter of the pipe to be replaced. As the pipe splitter is pulled, it is designed to split the existing pipe, and at the same time expand the split pipe into the surrounding soil. The expansion of the split pipe allows the pipe splitter to simultaneously pull a replacement pipe into place.